A typical analog telephone system sends and receives voice information to and from the PSTN (public switched telephone network) using a POTS (plain old telephone service) connection. An alternative approach for sending voice information has been developed using IP networks, sometimes referred to as VoIP (voice over IP). One common way to use VoIP is to provide voice information to a computer system (e.g., using a microphone) connected to the Internet. In one approach, the computer system converts the analog voice information to a digital data and sends the digital data as IP packets across the Internet to a recipient.
Some wireless handsets (e.g., some cell phones) provide both voice and data services through their corresponding wireless networks. The wireless handset establishes a wireless connection to the wireless network for transferring information and data. The wireless network is typically in turn connected to the PSTN and to the Internet. In this way, a user conducts voice calls through the wireless network and also can access data services such as e-mail or web browsing through the same wireless network.